REGULATORY CAPITAL (Summary of actual capital amounts and ratios) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total capital (to risk-weighted assets), Actual Amount	$ 350,403	$ 319,053
Total capital (to risk-weighted assets), Actual Ratio	12.50%	16.90%
Total capital (to risk-weighted assets), For Capital Adequacy Amount	$ 223,973
Total capital (to risk-weighted assets), For Capital Adequacy Ratio	8.00%
Tier 1 common equity (to risk-weighted assets), Actual Amount	$ 282,646	$ 249,655
Tier 1 common equity (to risk-weighted assets), Actual Ratio	10.10%	13.20%
Tier 1 common equity (to risk-weighted assets), For Capital Adequacy Amount	$ 125,985
Tier 1 common equity (to risk-weighted assets), For Capital Adequacy Ratio	4.50%
Tier 1 capital (to risk-weighted assets), Actual Amount	$ 308,769	$ 275,158
Tier 1 capital (to risk-weighted assets), Actual Ratio	11.00%	14.60%
Tier 1 capital (to risk-weighted assets), For Capital Adequacy Amount	$ 167,980
Tier 1 capital (to risk-weighted assets), For Capital Adequacy Ratio	6.00%
Tier 1 capital (to average assets), Actual Amount	$ 308,769	$ 275,158
Tier 1 capital (to average assets), Actual Ratio	9.40%	13.70%
Tier 1 capital (to average assets), For Capital Adequacy Amount	$ 131,087
Tier 1 capital (to average assets), For Capital Adequacy Ratio	4.00%
Total capital (to risk-weighted assets), Minimum for Capital Adequacy plus Capital Conservation Buffer Amount		$ 151,053
Total capital (to risk-weighted assets), Minimum for Capital Adequacy plus Capital Conservation Buffer Ratio		8.00%
Tier 1 common equity (to risk-weighted assets), Minimum for Capital Adequacy plus Capital Conservation Buffer Amount		$ 84,968
Tier 1 common equity (to risk-weighted assets), Minimum for Capital Adequacy plus Capital Conservation Buffer Ratio		4.50%
Tier 1 capital (to risk-weighted assets), Minimum for Capital Adequacy plus Capital Conservation Buffer Amount		$ 113,290
Tier 1 capital (to risk-weighted assets), Minimum for Capital Adequacy plus Capital Conservation Buffer Ratio		6.00%
Tier 1 capital (to average assets), Minimum for Capital Adequacy plus Capital Conservation Buffer Amount		$ 80,244
Tier 1 capital (to average assets), Minimum for Capital Adequacy plus Capital Conservation Buffer Ratio		4.00%
Metropolitan Commercial Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total capital (to risk-weighted assets), Actual Amount	$ 356,353	$ 314,226
Total capital (to risk-weighted assets), Actual Ratio	12.70%	16.70%
Total capital (to risk-weighted assets), For Capital Adequacy Amount	$ 223,858	$ 150,900
Total capital (to risk-weighted assets), For Capital Adequacy Ratio	8.00%	8.00%
Total capital (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Amount	$ 279,823	$ 188,625
Total capital (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Ratio	10.00%	10.00%
Tier 1 common equity (to risk-weighted assets), Actual Amount	$ 329,905	$ 294,880
Tier 1 common equity (to risk-weighted assets), Actual Ratio	11.80%	15.60%
Tier 1 common equity (to risk-weighted assets), For Capital Adequacy Amount	$ 125,920	$ 84,881
Tier 1 common equity (to risk-weighted assets), For Capital Adequacy Ratio	4.50%	4.50%
Tier 1 common equity (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Amount	$ 181,885	$ 122,606
Tier 1 common equity (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Ratio	6.50%	6.50%
Tier 1 capital (to risk-weighted assets), Actual Amount	$ 329,905	$ 294,880
Tier 1 capital (to risk-weighted assets), Actual Ratio	11.80%	15.60%
Tier 1 capital (to risk-weighted assets), For Capital Adequacy Amount	$ 167,894	$ 113,175
Tier 1 capital (to risk-weighted assets), For Capital Adequacy Ratio	6.00%	6.00%
Tier 1 capital (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Amount	$ 223,858	$ 150,900
Tier 1 capital (to risk-weighted assets), To be Well Capitalized under Prompt Corrective Action Regulations Ratio	8.00%	8.00%
Tier 1 capital (to average assets), Actual Amount	$ 329,905	$ 294,880
Tier 1 capital (to average assets), Actual Ratio	10.10%	14.70%
Tier 1 capital (to average assets), For Capital Adequacy Amount	$ 131,000	$ 80,050
Tier 1 capital (to average assets), For Capital Adequacy Ratio	4.00%	4.00%
Tier 1 capital (to average assets), To be Well Capitalized under Prompt Corrective Action Regulations Amount	$ 163,750	$ 100,063
Tier 1 capital (to average assets), To be Well Capitalized under Prompt Corrective Action Regulations Ratio	5.00%	5.00%

The amount of total capital minimum for capital adequacy plus capital conservation buffer.

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Percentage of capital minimum for capital adequacy plus capital conservation buffer to risk weighted assets.

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Percentage of common equity tier one capital minimum for capital adequacy plus capital conservation buffer to total risk-weighted assets, as defined by regulatory framework.

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Percentage of common equity tier one capital required for capital adequacy to risk weighted assets ratio.

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The amount of common equity tier one minimum for capital adequacy plus capital conservation buffer risk-based capital, as defined by regulatory framework.

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Tier 1 leverage minimum for capital adequacy plus capital conservation buffer as defined in the regulations.

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Percentage of tier one leverage minimum for capital adequacy plus capital conservation buffer to average assets, as defined by regulatory framework.

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Tier 1 risk based minimum for capital adequacy plus capital conservation buffer as defined in the regulations.

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Percentage of tier one risk based minimum for capital adequacy plus capital conservation buffer to total risk-weighted assets, as defined by regulatory framework.

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The amount of total capital as defined in the regulations.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Percentage of Common Equity Tier One Risk-based Capital to total risk-weighted assets, as defined by regulatory framework.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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